The findings here suggest that both NAFLD and the MS very early in development have a common inciting mechanism(s)-most likely IR. Accordingly, the early concurrent temporal results are consistent with the concept that NAFLD is a hepatic manifestation of the IR associated with the MS. They do not exclude the possibility that once some liver functional adjustments take place, several aspects of the MS are bolstered further, perhaps via intensified heightening of IR.

Background: Two facts are generally recognized: (1) development of nonalcoholic fatty liver disease (NAFLD) is consistently linked to insulin resistance which has dietary implications and (2) circulating alanine aminotransferase (ALT) levels are reasonable markers predicting NAFLD status. In a recent cross-sectional study employing nondiabetic subjects, ALT values rose steadily within a normal range early in the life cycle but begin decreasing steadily around age 65 years. Objectives: Because of important nutritional implications, the association between ALT levels and aging in a significantly larger population of healthy volunteers was examined for corroborative purposes. A secondary goal was to gain further knowledge concerning mechanisms behind any age-related decline in ALT activity. Methods: Baseline data from over 10,000 physician-approved, nondiabetic subjects (age 21-84 years) of both genders who had volunteered for previous clinical investigations were assessed. Results: In this cross-sectional examination, the line of best fit (weighted) for average yearly circulating ALT levels displayed an upward surge from ages 21 to 64 years with a discernible steady downward decline around 65 years-mimicking earlier results. Examining linear lines of correlation in the younger and older age groups, the following calculations were determined: a significant positive slope for 21 to 64 years, r ¼ 0.42, n ¼ 44, p < 0.005, and a trending negative slope for 65 and beyond, r ¼ À0.43, n ¼ 20, p < 0.057. Using this same datum base, the correlations between age and fasting blood glucose (FBG) mimicked the ALT results by once more showing a similar upward rise in the younger and a steady decline the older group of volunteers. Conclusions: A paradoxical downward age-related (! 65 years) decline of circulating ALT coinciding with a comparable steady decrease in FBG levels was replicated in a larger population of volunteers. The close association of these two chemistries along with other findings suggest that altered glucose-insulin metabolism may participate via "survivor bias" in the ubiquitously found age-related decline of serum ALT-suggesting that nutritional measures could advance optimal health over the life-span.Abbreviations: ALT: alanine aminotransferase; AST: aspartate aminotransferase; FBG: fasting blood glucose; IR: insulin resistance; MS: metabolic syndrome; NAFLD: nonalcoholic fatty liver disease ARTICLE HISTORY

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SummaryIt is generally accepted that ingestion of sucrose in large quantities elevates blood pressure (BP). Less certain is whether starch and other refined carbohydrates (CHO) have similar effects. Using spontaneously hypertensive rats (SHR) and normotensive control rats (WKY), we show that glucose, fructose, and starch fed to rats either in solution or in dry form elevate BP to a similar degree as sucrose. The changes in BP brought on by various refined CHO were greater in SHR than in WKY. The elevations did not consistently correlate with differences in body weight, amount of dry matter or fluid intake, the quantities of sodium and potassium ingested, or to changes in the various blood chemistries examined. We conclude that other refined CHO (glucose, fructose, and starch) like sucrose raise BP significantly. This effect on BP is rapid (within days) and reversible, at least to some extent.Key Words: carbohydrates, effects on blood pressure, spontaneously hypertensive rats, effect of CHO, macronutrients Excess ingestion of sucrose, a disaccharide of glucose and fructose, elevates blood pressure (BP) in rats [1]. However, it is uncertain whether simple carbohydrates (CHO) other than sucrose cause similar BP increases. Because previous studies have been inconsistent, glucose, fructose, and starch individually cannot be conclusively implicated in a BP response. For example, Hall and Hall [2] found that addition of glucose to a saline drinking solution elevates BP but was significantly less hypertensive than the combination of sucrose plus saline. Honey, which is composed of fructose, did not elevate BP when added to saline. Beebe

In the present investigation, a cross-sectional analysis was carried out over a wide age range of subjects. It is noteworthy that fasting glucose levels and the other major elements of metabolic syndrome did not change significantly with advancing age. These results demonstrate that decreasing insulin resistance and fasting glucose levels may be an important way to overcome the adverse effects and perturbations of advancing age-induced consequences of metabolic syndrome.